Nokia is working on Android 10 for the 9 PureView. This is evidenced by the leaked build of the ROM for this phone posted to its XDA forum. This version of the OS is believed to be part of official development from the brand, and also exists for other devices such as the 7.1 and 6.1 Plus.
https://www.notebookcheck.net/An-early-Android-10-build-for-the-Nokia-9-PureView-gets-leaked.441287.0.html